hub: stop sharing the embedded descriptor map across registries#632
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NewRegistryOfKnownResources and NewKVLocal wrapped resourcedescriptors.KnownDescriptors() — the package-global map — directly into a KVMap. Different Registry instances therefore held their own RWMutex but wrote into the same underlying Go map on KVMap.Set. The pool spins up one registry per cluster UID (PoolSize=1024); when several clusters concurrently discovered CRDs that weren't in the embedded set, those Set calls raced on the shared map. In Go that is a "fatal error: concurrent map writes" — not a silent corruption but a process crash. Introduce NewKVMapFromKnown(), which copies the known-descriptors map into a fresh map before wrapping it in a KVMap, and use it from both construction paths. KnownDescriptors() itself is unchanged; out-of-tree pool factories that share the global map should migrate to this helper. Signed-off-by: Tamal Saha <tamal@appscode.com>
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Summary
NewRegistryOfKnownResourcesandNewKVLocalboth wrappedresourcedescriptors.KnownDescriptors()— the package-global map — directly into aKVMap. EachRegistryheld its ownRWMutex, butKVMap.Setwrote into the same underlying Go map under different locks.PoolSize = 1024clusters, a CRD discovery from cluster A and one from cluster B can hitSetsimultaneously and trigger Go's runtimefatal error: concurrent map writes— a process crash, not silent corruption.NewKVMapFromKnown()which copies the map before wrapping, and use it from both in-tree construction sites.KnownDescriptors()is unchanged so out-of-tree consumers keep working; any pool factory that constructs aKVMapdirectly fromKnownDescriptors()should migrate to this helper.Test plan
make unit-testsgo test -race ./hub/...— exercise the registry concurrently via a small in-package test that spins multiple goroutines callingSeton different registries built fromNewRegistryOfKnownResources. (Optional follow-up if not yet present.)🤖 Generated with Claude Code